A suspension system of a vehicle is a device for absorbing shocks transmitted from a road. The suspension system typically includes, for each wheel, a knuckle that receives the wheel with the knuckle being supported from below by a lower trailing arm and from above by a shock absorber cooperating with a coil spring.
The lower arm is coupled to the sub frame of the vehicle through front and rear bushings. When the vehicle is running in a straight line, shape of the front bushing and the rear bushing are oppositely distorted. That is, when a shock is transferred to a vehicle body in a rearward direction, as shown in FIG. 3A, the front bushing is outwardly distorted and the rear bushing is inwardly distorted. To improve riding comfort, distortions of the front and rear bushings must be maximnized.
When the vehicle is cornering, lateral force is transmitted to the lower arm, so that in the case of cornering to the right the front and rear bushings are inwardly distorted at the same time. Under these conditions, for a cornering stability, distortions of the rear and front bushings must be minimized. However, the conventional lower arm cannot satisfy the opposite requirements for straight line and cornering operation at the same time.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art that is already known to a person skilled in the art.